Answer:
507.5 mm squared
Step-by-step explanation:
To find the surface area, find the area of each surface and add the areas together.
The surface of the three triangle sides is A = 1/2*b*h where b = 17 and h = 15. So the area is A = 1/2*15*17 = 127.5.
Since there are three, multiply this by 3.
3*127.5 = 382.5
Add this area to the base which is already give to you as 125.
382.5 + 125 = 507.5
